The 4.5" anti-aircraft gun was an adoption of the 4.5" Naval gun, the naval gun was chosen as there was there was no prospect of the 4.7" being developed and put into production soon and as these guns were planned to be placed near naval bases ammunition supplies would be assured and so in 1938 the 4.5" anti-aircraft gun was approved for land service. Some guns were fitted with a mild steel shield and some guns were placed at the coast to be used in a dual anti-aircraft / coastal defence role. By 1944 the guns were being replaced by the 5.25" gun but the weapons were not declared obsolete until 1951.

4.5" Anti-Aircraft gun data

Weight of gun/breech

6,180lb

Total length

211.75"

Length of bore

45 cal

Rifling

32, 1/25

Elevation

0 - +80 degrees

Traverse

360 degrees

Weight in action

33,040lb

Rate of fire

8rpm

4.5" Anti-Aircraft gun ammunition data

HE Shell weight

58lb

Muzzle velocity

2,400fps

Max horizontal range

22,800 yards

Max ceiling

44,000 feet

Production of the 4.5" Anti-Aircraft Gun by year

Pre-War

Sep-Oct 1939

1940

1941

1942

1943

1944

1945 (May)

Guns

185

116

141

56

2

-

-

-

Mountings

156

115

182

21

-

-

-

-

Platforms

-

-

14

4

1

-

-

-

Sources - British & American Artillery of WWII, AVIA 22 456 - 514

Comments (1)

4.5in AA guns

1
Monday, 05 July 2010 01:50

Allan Long

I was in 81st HAA Regt RA at Fenham Barracks Newcastle upon Tyne in 1953-54, we still had these guns` at Fenham Barracks and at the regimental gunsites` at Willington Square Wallsend, and Seaburn south of Sunderland. 81st HAA was disbanded in 1954 when the UK AA Command was disbanded.